Markdown Formatter

Transforms plain text or markdown into well-structured, reader-friendly markdown. The goal is to help readers quickly grasp key points, highlights, and structure — without changing any original content.

Core principle: Only adjust formatting and fix obvious typos. Never add, delete, or rewrite content.

User Input Tools

When this skill prompts the user, follow this tool-selection rule (priority order):

1. Prefer built-in user-input tools exposed by the current agent runtime — e.g., AskUserQuestion, request_user_input, clarify, ask_user, or any equivalent.
2. Fallback: if no such tool exists, emit a numbered plain-text message and ask the user to reply with the chosen number/answer for each question.
3. Batching: if the tool supports multiple questions per call, combine all applicable questions into a single call; if only single-question, ask them one at a time in priority order.

Concrete AskUserQuestion references below are examples — substitute the local equivalent in other runtimes.

Script Directory

Scripts in scripts/ subdirectory. {baseDir} = this SKILL.md's directory path. Resolve ${BUN_X} runtime: if bun installed → bun; if npx available → npx -y bun; else suggest installing bun. Replace {baseDir} and ${BUN_X} with actual values.

Preferences (EXTEND.md)

Check EXTEND.md in priority order — the first one found wins:

If none found, use defaults — no first-time setup required for this skill.

EXTEND.md supports:

Usage

The workflow has two phases: Analyze (understand the content) then Format (apply formatting). Claude performs content analysis and formatting (Steps 1-5), then runs the script for typography fixes (Step 6).

Workflow

Step 1: Read & Detect Content Type

Read the user-specified file, then detect content type:

If Markdown detected, use AskUserQuestion to ask:

Detected existing markdown formatting. What would you like to do?

1. Optimize formatting (Recommended)
   - Analyze content, improve headings, bold, lists for readability
   - Run typography script (spacing, emphasis fixes)
   - Output: {filename}-formatted.md

2. Keep original formatting
   - Preserve existing markdown structure
   - Run typography script only
   - Output: {filename}-formatted.md

3. Typography fixes only
   - Run typography script on original file in-place
   - No copy created, modifies original file directly

Based on user choice:
- Optimize: Continue to Step 2 (full workflow)
- Keep original: Skip to Step 5, copy file then run Step 6
- Typography only: Skip to Step 6, run on original file directly

Step 2: Analyze Content (Reader's Perspective)

Read the entire content carefully. Think from a reader's perspective: what would help them quickly understand and remember the key information?

Produce an analysis covering these dimensions:

2.1 Highlights & Key Insights
- Core arguments or conclusions the author makes
- Surprising facts, data points, or counterintuitive claims
- Memorable quotes or well-phrased sentences (golden quotes)

2.2 Structure Assessment
- Does the content have a clear logical flow? What is it?
- Are there natural section boundaries that lack headings?
- Are there long walls of text that could benefit from visual breaks?

2.3 Reader-Important Information
- Actionable advice or takeaways
- Definitions, explanations of key concepts
- Lists or enumerations buried in prose
- Comparisons or contrasts that would be clearer as tables

2.4 Formatting Issues
- Missing or inconsistent heading hierarchy
- Paragraphs that mix multiple topics
- Parallel items written as prose instead of lists
- Code, commands, or technical terms not marked as code
- Obvious typos or formatting errors

Save analysis to file: {original-filename}-analysis.md

The analysis file serves as the blueprint for Step 3. Use this format:

# Content Analysis: {filename}

## Highlights & Key Insights
- [list findings]

## Structure Assessment
- Current flow: [describe]
- Suggested sections: [list heading candidates with brief rationale]

## Reader-Important Information
- [list actionable items, key concepts, buried lists, potential tables]

## Formatting Issues
- [list specific issues with location references]

## Typos Found
- [list any obvious typos with corrections, or "None found"]

Step 3: Check/Create Frontmatter, Title & Summary

Check for YAML frontmatter (--- block). Create if missing.

Title Generation

Whether or not a title already exists, run the title optimization flow unless auto_select_title is set.

Preparation — read the full text and extract:
- Core argument (one sentence: "what is this article about?")
- Most impactful opinion or conclusion
- Reader pain point or curiosity trigger
- Most memorable metaphor or golden quote

Generate candidates using formulas from references/title-formulas.md:

1. Select the 2-3 best-matching hook formulas based on the article's content, tone, and structure (see "When to pick each formula" in the reference)
2. Generate 1-2 straightforward titles (descriptive or declarative, no formula — clear and accurate)
3. If the user specifies a direction (e.g., "make it suspenseful"), prioritize that direction
4. Total: 4-5 candidates

Present via AskUserQuestion:

Pick a title:

1. [Hook title A] — (recommended) [formula name]
2. [Hook title B] — [formula name]
3. [Hook title C] — [formula name]
4. [Straightforward title D] — straightforward
5. [Straightforward title E] — straightforward

Enter number, or type a custom title:

Put the strongest hook first and mark it (recommended). See references/title-formulas.md for principles and prohibited patterns.

If the first line is an H1, extract it to frontmatter and remove it from the body. If frontmatter already has a title, include it as context but still generate fresh candidates — the existing title may be weak.

Skip behavior: If auto_select: true or auto_select_title: true, skip the user prompt and use the top candidate directly.

Summary Generation

Generate two versions directly (no user selection), both stored in frontmatter:

Principles:

• Convey core value to the reader, not just the topic
• Use concrete details (numbers, outcomes, specific methods) over vague descriptions
• summary should be punchy and self-contained; description can expand with supporting details
• If frontmatter already has summary or description, keep the existing one and only generate the missing field

Prohibited patterns:

• "This article introduces...", "This article explores..."
• Pure topic description without value proposition
• Repeating the title in different words

Once the title is in frontmatter, the body should NOT contain an H1 (avoid duplication).

Step 4: Format Content

Apply formatting guided by the Step 2 analysis. The goal is making the content scannable and the key points impossible to miss.

Formatting toolkit:

Formatting principles — what NOT to do:
- Do NOT add sentences, explanations, or commentary
- Do NOT delete or shorten any content
- Do NOT rephrase or rewrite the author's words
- Do NOT add headings that editorialize (e.g., "Amazing Discovery" — use neutral descriptive headings)
- Do NOT over-format: not every sentence needs bold, not every paragraph needs a heading

Formatting principles — what TO do:
- Preserve the author's voice, tone, and every word
- Bold key conclusions and core takeaways — the sentences a reader would highlight
- Extract parallel items from prose into lists only when the structure is clearly there
- Add headings where the topic genuinely shifts — prefer vivid, specific headings over generic ones (e.g., "3 天搞定 vs 传统方案" over "方案对比")
- Use tables for comparisons or structured data buried in prose
- Use blockquotes for golden quotes, memorable statements, or important warnings
- Fix obvious typos (based on Step 2 findings)

Step 5: Save Formatted File

Save as {original-filename}-formatted.md

Backup existing file:

if [ -f "{filename}-formatted.md" ]; then
  mv "{filename}-formatted.md" "{filename}-formatted.backup-$(date +%Y%m%d-%H%M%S).md"
fi

Step 6: Execute Typography Script

Run the formatting script on the output file:

${BUN_X} {baseDir}/scripts/main.ts {output-file-path} [options]

Script Options:

Examples:

# Default: spacing + emphasis enabled, quotes disabled
${BUN_X} {baseDir}/scripts/main.ts article.md

# Enable all features including quote replacement
${BUN_X} {baseDir}/scripts/main.ts article.md --quotes

# Only fix emphasis issues, skip spacing
${BUN_X} {baseDir}/scripts/main.ts article.md --no-spacing

Script performs (based on options):
1. Fix CJK emphasis/bold punctuation issues (default: enabled)
2. Add CJK/English mixed text spacing via autocorrect (default: enabled)
3. Replace ASCII quotes with fullwidth quotes (default: disabled)
4. Format frontmatter YAML (always enabled)

Step 7: Completion Report

Display a report summarizing all changes made:

**Formatting Complete**

**Files:**
- Analysis: {filename}-analysis.md
- Formatted: {filename}-formatted.md

**Content Analysis Summary:**
- Highlights found: X key insights
- Golden quotes: X memorable sentences
- Formatting issues fixed: X items

**Changes Applied:**
- Frontmatter: [added/updated] (title, slug, summary)
- Headings added: X (##: N, ###: N)
- Bold markers added: X
- Lists created: X (from prose → list conversion)
- Tables created: X
- Code markers added: X
- Blockquotes added: X
- Typos fixed: X [list each: "original" → "corrected"]

**Typography Script:**
- CJK spacing: [applied/skipped]
- Emphasis fixes: [applied/skipped]
- Quote replacement: [applied/skipped]

Adjust the report to reflect actual changes — omit categories where no changes were made.

Notes

• Preserve original writing style and tone
• Specify correct language for code blocks (e.g., python, javascript)
• Maintain CJK/English spacing standards
• The analysis file is a working document — it helps maintain consistency between what was identified and what was formatted

Extension Support

Custom configurations via EXTEND.md. See Preferences section for paths and supported options.